The objectives of this program are twofold: 1. Sustain and extend a collaboration among participants in an interdisciplinary program that will provide a broad, integrated approach to cancer research with emphasis focused on the cell plasma membrane. 2. Characterize the regulatory features of membrane structure and function that operate in communicating and controlling events of the proliferation process. To accomplish these goals we are integrating the highly relevant areas of expertise contributed by the program participants. The research areas covered include: thermodynamic and physical characterization and membrane phase transitions, regulation of cellular transport, regulatory roles of cyclic nucleotides and their metabolism, cellular and molecular recognition, intercellular communication through gap junctions, biological effectors of cell movement, chemical composition and ultrastructure of the membrane, immunological aspects of cellular responses, and virus induced membrane alterations. These investigations are utilized in defining the characteristics of membrane and cellular function associated with malignant transformation. BIBLIOGRAPHIC REFERENCES: Haddox, M.K., Furcht, L.T., Gentry, S.R., Moser, M.E., Stephenson, J.H. and Goldberg, N.D. Periodate-induced Elevation of Cyclic GMP Levels in Mouse and Guinea Pig Splenic Cells in Association with Mitogenesis. Nature, 262:146, 1976. Glass, D., Carr, D., Gerrard, J., Townsend, D., White, J., and Goldberg, N.D. Guanylate Cyclase Activation by Prostaglandin Endoperoxide, Arachidonic Acid, and Closely Related Fatty Acids. Fed. Proc. 35, 456, 1976.